If you are using the wrong gasket between the carburetor and the intake manifold (too thin, 3mm instead of 8.5mm) the choke thermostat pushrod will effectively be too long.
I finally got all parts to make a serious job.
The two studs with crenelated nuts and brass conical wahers are for my exhaust manifold as I plan to improve the intake/exhaust manifolds combo installation...
Now, just have to wait for better weather conditions. It's a little bit too much cold for me :)